Pentachlorophenyl carbanilates



. 3,024,269 PENTACHLOROPHENYL CARBANILATES Eric Barthel, In, and Raymond W. Luckenbaugh, Wilmington, and Jerry A. Nelson, Newark, Del., assignors to E. I. du Pont de Nemours and Company, Wilmington, Del., a corporation of Delaware No Drawing. Filed Mar. 18, 1957, Ser. No. 646,559

1 Claim. (Cl. 260-471) This invention relates to new compounds formula:

( I Y H 9 wherein X is halogen or alkyl of 1 through 4 carbon atoms; Y is hydrogen, isocyanato (--NCO) or mtro (NO and n is a whole integer of 1-3, that IS, 1, 2 or 3; and methods for their preparation. a

The compounds of the invention can be prepared by various conventional means. For example, they can be prepared by the reaction of stoichiometric amounts of a substituted phenyl isocyanate and pentachlorophenol m the presence of a catalytic amount of a tertiaryamine base, such as pyridine or triethylamine, in accordance with the following equation:

of the Pyridine AI-NCO H EMT-ya;

O Ar-NIIgO- The reaction is advantageously carried on in an organic liquid media that is inert to the other materials present. Suitable organic liquids for this purpose are benzene, toluene, xylene and dioxane. The reaction can be carried out at a temperature in a range of about 5 to 130 C.

' The substituted phenylisocyanates used in the synthesis of our compounds can be prepared by conventional methods, such as by the reaction of a substituted aniline with phosgene.

Illustrative of the compounds of our invention are the pentachlorophenyl esters of the following carbanilic acids.

A United States Patent 0 Patented Mar. 6, 1962 Dust compositions containing from 5 to 30% by weight of the active ingredient are effective in controlling the growth of seeds when applied atrates of 5 to 100 pounds per acre of active ingredient. I

These compounds can be formulated into compositions suitable for application by admixing one or more of such compounds in herbicidally effective amounts with a liquid or powdered solid conditioning agent of the kind used and referred to in the art as a pest control adjuvant or modifier. Thus the active compounds can be formulated with one or more of the pest control adjuvants set forth in Todd Patent No. 2,655,447. In general, from about 0.5% to by weight of the active ingredient is present in our compositions.

The preferred compositions are in the form of dusts or wettable powders. They are compounded to be homogeneous and free-flowing by admixing the active compounds or compounds with finely divided solids such as talcs, natural clays, pyrophyllite, diatomaceous earth, walnut shell flour, redwood flour and other inert solid conditioning agents or carriers of the kind conventionally employed in preparing pest-control compositions in dust form.

Liquid compositions are prepared in the usual way by forming a solution or suspension of one or more of the active compounds with a suitable liquid pest-control adjuvant such as those set forth in the aforementioned Todd patent.

Herbicidal compositions of the invention, whether in the form of solids or liquids can also contain a surface active agent of the kind sometimes referred to in the art as a wetting, dispersing or emulsifying agent. Generally, the surface active agents will comprise not more than 5 to 10 percent by weight of a composition and in some compositions the percentage will be considerably less than 1 percent. A detailed list of such agents is set forth in an article by McCutcheon in Soap and Chemical Specialties," volume 31, No. 7, pages 50 to 61; No. 8, pages 48 to 61; No. 9, pages 52 to 67; and No. 10, pages 48 to 67 (1955). See also 'McCutcheon in Chemical Industries, November 1947, page 811 entitled Synthetic Detergents and Bulletin E-607 of the Bureau of Entomology and Plant Quarantine of the US. Department of Agriculture.

Other pest-control agents such as insecticides, fungicides and other herbicides can also be included in the herbicidal compositions of our invention. In fact, perhaps the best of our herbicidal compositions are those that contain in addition to an active compound of the type represented by Formula 1, one or more of the well known herbicidally active aryl aliphatic ureas, such as those described in Todd Patent Nos. 2,655,444 through 2,655,447.

The compositions containing pentachlorophenyl carbanilic acid ester and an aryl aliphatic urea can be made by mixing the various ingredients in any desired ratio to give a suitable formulation. On the other hand it is often convenient to prepare both the ester and urea simultaneously by reacting only part of the aryl isocy-anate with pentachlorophenol and the remainder with an appropriate amine. The reaction product consists of a mixture of the ester and the urea. The relative proportions of the two ingredients are determined by the proportion of the isocyanate that is reacted with the pentachlorophenol and the amine.

In order to more clearly illustrate our invention, the following examples are given in addition to those set forth above:

EXAMPLE 1 A mixture of 26.6 parts by weight of pentachlorophenol, 200 parts of dry benzene and 0.2 part of pyridine is warmed to 40" C. to obtain a solution. To this solution is added 15.4 parts by weight of p-chlorophenylisocyanate dissolved in 50 parts of benzene. The solution is then refluxed on a steam bath overnight, cooled and the precipitate removed by filtration.

After washing with n-pentane and air drying, a total of 30.9 parts of crude pentaehlorophenylester of pchlorocarbanilic acid-is formed. This is found to have a melting point of 159.5-174" C. Subsequently crystallizations from benzene and then from ethylacetate yield white needles of pure pentachlorophenylester of p-chlorocarbanilic acid, having a melting point of 164.5-173' C.

AnaIysis.-Calc'd for C H CI NQ: Cl, 50.66; N, 3.33. 'Found: Cl, 50.55; N, 3.30.

EXAMPLES 2-17 The procedure of Example 1 is used for preparing the following pentachlorophenylesters of carbanilic acids by substituting for the p-chlorophenylisocyanate of Example 1 the various aryl isocyanates in the listed amounts.

Ex. Weight Name of product is the N Name 01 lsocyanste of impentachlorophenylester 01- 2. m-Ohlorophenyl- 15. 4 m-Ohloroearbanilic acid. 3.-. 3,4-diehloro-phenyl-. 18. 8 3,4-dlehloroearbanilie add. 4.-. 2,4 5-trlchloro-phneyl-.-- 22. 3 2,4,5-trichlorocarbanlllc add. 5--- p- 01 l- 13.8 p-Methylearbanllle acid.

in To y 13.3 m-Methylcarbanilie acid.

16. 8 B-gharMmethylearbanflic 15. 9 p-Ethylcsrbarulle add. 17.3 p-Iso ropylmrbanlllc aeld. 15.9 3,4 methylmrbanlllc acid. 19. 4 3-tlt hlmlsopropybmrbenic 12.--- 4-ehloro-3-nltrophenyl-. 19. 9 4 20m 8 nltrocarbanllle 13.- m-Fluoropheny1-- 13. 7 m-Fluorocarbanillc acid. 14.--- p-Bromophenyl--. 19.8 p-Bromocsrbanllic acid. 16..-- p-Iodophenyl-. 24. 5 p-Iodooarbanlllc acid. 16.--- 2,5-d1bromophenyl-.. 27. 7 2,5-dibromocarbanlllc acld. 17...- 3-lsocyanato-p-to yl-...-- 17. 4 4 methylear snllle These products are in most instances crystalline solids that are insoluble in water and only slightly soluble in most hydrocarbon solvents.

EXAMPLE 18 Wettable Powder Compositions The following wettable powder compositions are prepared by combining the dry ingredients listed, blending in a ribbon blender, micropulverizing in a hammer mill until substantially all of the product is below 50 microns, and then reblending the product in a ribbon blender to give a free flowing powder that is readily dispersed in, water to form dilute sprayable formulations.

Percent Pentachlorophenylester of p chlorocarbsnilic Pentachlorophenylester of 3,4 dichlorocarbanilic acid 80 5 Dry Attapulgite 16.25 Alkyl aryl sulfonate 1.75 Lignin sulfonate 2.0

The following dust compositions are prepared by mixing the active component with the absorptive diluent, micropulverizing the mixture, adding the principal diluent and then blending in a ribbon blender.

Percent Pentachlorophenylester of m-chlorocarbanilic acid 10 Dry Attapulgite l0 Talc 80 Pentachlorophenyl ester of 2,4,5-trlchlorocarbanilic 80 acid Dry Attapulgite 20 Pyrophyllite 60 Pentachlorophenyl ester of p-bromocarbanilic acid 10 D y Ampulgite 10 Pyrophyllite 80 Pentachlorophenyl ester of 3,4-dichlorocarbanilic acid 10 3-(3,4-dichlorophenyl)-1,l-dimethylurea 10 Dry Attapulgite 20 Talc Pentachlorophenyl ester of p-chlorocarbanilie acid 5 3-(p-chlorophenyl)-l,l-dimethylurea l5 0 Dry Attapulgite 20 Talc 60 Pentachlorophenyl ester of p-ethylearbanilic acid 15 3-(p-ethylphenyl)-I-methyl-l-isopropylurea 5 Dry Attapulgite l0 Pyrophyllite These compositions, when dusted by hand on weeds 6 growing around a warehouse, give extremely etiective weed control.

EXAMPLE 20 Water-Dispersions 55 The following water dispersions are made by milling in a ball mill or in a sand mill the listed components with water. The compositions are as follows:

A 0 Percent Pentschlorophenyl ester of carbanilic acid 30 Hydrated Attapulgite 1.75 Lignin sulfonate 15 Water 52.75

1.0 Sodium pentachlorphenate 0.5

Pentachlorophenyl ester of m-fluorophenylcarba- Pentachlorophenyl ester of 3-isocyano-4-methylnilic acid 40 carbanilic acid 40 Hydrated Attapulgite 1.75 Hydrated Attapulgite 39 Lignin sulfonate 5 5 Alkyl aryl sulfonate 1 Water 52.75 Sodium sulfate, anhydrous 20 Sodium pentachlorphenate 0.5 C

These compositions are then sprayed from a tractor mounted sprayer on a field planted with cotton seed. m gg fig figg ester of more 3 mtm'carb 30 This1 treatmelnt is found to give excellent pre-emergcnce Hydrated Ampulgite 55 wee comm Sodium sulfate EXAMPLE 21 D Oil Dispersions I The following oil dispersions are prepared by milling, 15 q pp ny ester of 3 r0- -1sopr0pylsuch as in a sand mill or a ball mill, the listed ingredients: carbamllc acid 1-(m-tolyl)-l,3,3 tnmethylurea A Hydrated Attapulgite 39 Percent Alkyl aryl sulfonate l Pentachlorophenyl ester of p-chlorocarbamhc acid 25 20 s i f anhydrous 20 Diesel oil 75 E B Pentachlorophenyl ester of 2,5-dibromocarbanilic Pentachlorophenyl ester of 3,4-dichlorocarbanilic acid 10 acid 25 25 3-(2,5-dibromophenyl)-3-methy1-1-butylurea 20 Diesel oil 75 Hydrated Attapulgite 55 These oil dispersions, when sprayed from a railroad Sodmm sulfate anhydrous 15 spray car along the railroad right-of-way, give excellent These Pellets are Scattered y hand on clumps of bindcontrol of the weeds rowin on th railroad b nkweed growing in a cultivated field. It is found that this ment. treatment gives excellent control of this weed.

EXAMPLE 22 What is claimed is: Pellet Compositions Pentachlorophenyl ester of parachlorocarbanilic acid.

The following pellet compositions are prepared by inmtgfiemmes filed in the file of this Patent timatcly mixing the listed ingredients with a very small UNITED STATES PATENTS amount of water in a ribbon blender, and then extruding 1 the mass under high pressure through a inch diameter Baumgarmer 1952 2,658,071 Beman Nov. 3, 1953 ye whlle cutting the extruded material into short lengths. 2,734,911 Strain Feb. 14, 1956 The mmposltlons are as 40 2,858,328 Beaver et a1. Oct. 28, 1958 A 2,951,786 Pullen et a1. Sept. 6, 1960 Percent OTHER REFERENCES Pentachlorophenyl ester of p-iodocarbanilic acid 40 Bensteim 12, 327 (1929). Hydrated Attapulslte 39 Thompson: Botanical Gazette, 107,504 (1946). AlkYl W sulfonate 1 Immelman et al.: Chem. Abst., 45, 3980 1951 Sodium sulfate, anhydrous 20 

